As of last year, 700 sqft of Honda’s roadside solar generators produce enough hydrogen in one week to fuel one car for 175 miles. Clearly this is not enough, but it could be if you use more land.

(700 sqft of solar arrays) x (7 days) = 175 miles

equivalent to

(1 acre of solar arrays) x (1 day) = 1556 miles

If we assume that cars get about 25 mi/gallon of gas, then each acre produces the equivalent of about 62 gallons of gas per day. If gas costs $3/gallon, and hydrogen is priced to drive the same distance for the same cost, then each acre produces about $187/day in sales. That’s $68,140/year. Maintaining solar arrays is pretty cheap, let’s assume $5000/year/acre. If we discount the implied cash flow using a real rate of 5%, the value is $1.26m/acre. Obviously, an acre of solar arrays is expensive. Today, the cost would be about $1.5m, and exceed the net present value. But not for long!

Technology is progressing at a rapid rate. Today’s 6% efficiency may improve to 30% within 10 years. If the efficiency rises to 30%, the negative net present value of producing hydrogen turns positive. Very positive: $5 million per acre.

And don’t forget, for added upside you can install a wind farm over your solar arrays, and produce with both. Own some land.